1. Field
Example embodiments relate to methods of preparing high refractive index nanoparticles, nanoparticles prepared by the methods, and/or photonic crystal devices using the nanoparticles.
2. Description of the Related Art
High refractive index nanoparticles, which strongly interact with light, are important materials in the optical field. Accordingly, many attempts to use high refractive index nano particles, e.g., TiO2, CdS, SnO2, ZnO, ZrO2, and CdSe, in the optical field have recently been made.
From among high refractive index materials, Group II-VI or III-V compound semiconductors may control bandgaps by using a chemical method or a quantum confinement method, and thus are considered desirable optical materials. Although research on such materials has been actively conducted, existing materials are nanoparticles having a size equal to or less than 50 nm or particles having a size close to a micro size. Accordingly, there is a limitation in preparing nanoparticles having a uniform mesoscopic size distribution.
Because particles having a mesoscopic size may interact with light in a visible band, the particles having a mesoscopic size may be used in various fields including displays. For example, particles having a mesoscopic size may constitute photonic crystals by using self-assembly. Photonic crystals have a grid structure in which two or more materials having different refractive indices are regularly arranged in a two-dimensional (2D) or three-dimensional (3D) manner. Such photonic crystals having a grid structure have a photonic bandgap through which light having a specific wavelength may be blocked or passed due to a periodic distribution of refractive indices.